Not sure if you're a troll or have just forgotten to take the dried frog pills but going to given you the benefit of the doubt and assume it's the latter.
The problem with your metaphor about the boat anchor is that anchors provide stability in stormy seas and prevent your boat from moving when you want it to stay put. They can also be drawn up when you want to go somewhere.
We don't leave the day Article 50 is involved, we leave at the earliest two years afterwards. That deadline could be extended but for many reasons such as electoral cycles and future planning of EU programs that isn't going to happen. You could pretend that it is otherwise but then you're inviting the UK to experience a world of pain as every country in the EU retaliates (it's still our single biggest trading partner) and every other sane country in the world wonders if being mates with the new nutter on the block who thinks nothing of breaking contracts and going back on agreements is such a good idea.
Just sign a trade deal the next day? You do realise those things take years to negotiate and the UK doesn't have the personal to negotiate one much less do dozens or hundreds with the whole world simultaneously and if the other side thinks they have an advantage over the UK that deal might be a lot less sweet than you expect. Legally the UK isn't suppose to be negotiating with other countries until we leave i.e. in two years. Lets not forget the financial markets in France and Germany have a lot to gain if they can managed to sideline London. If they can convince their governments they can make up the difference in any trade lost to the UK they might actually push for quite harsh terms. If London wants to keep trading with the rest of the EU on passporting terms that is going to mean accepting everything the Brexiters said they rejected the EU for but now we'll have no control over how it is shaped in the future and the financial sector is the single biggest contributor to the tax base in the UK.
Frau Merkel needs the agreement of 26 other heads of state for the EU side of the arrangement. That's 26 very different cats with very different agendas. As much as rags like the Daily Heil like to portray the EU as a neo-Nazi plot to take over Europe (and then the World!) she isn't a dictator and can't force them to obey her every diktat.
EU directives and 'laws' are enacted in the UK via acts of parliament. The day after we leave the EU all those laws will still be in place and personally, I don't want the safety laws saying the dyes used in children's clothing has to be non-toxic and the clothes themselves have to be non-flammable to be repealed. Can you give me an example of the ten you would repeal first? Besides, trading with the EU means making things to EU standards anyway so you're getting rid of a lot less regulation than you think.
The Supreme Court has never been 'supreme'. It was the house of lords which was the 'supreme' court in the land before we joined the EU but we were still members of the ECHR so it isn't as 'supreme' as you imagine or would like it to be.
A good rant does wonders to get the blood flowing in the morning.